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Journal of Reconstructive Microsurgery Jun 2024Fasciocutaneous free deltoid flaps are used to reconstruct hand, foot, and maxillofacial defects. Although anatomical studies of this flap pedicle have been performed...
BACKGROUND
Fasciocutaneous free deltoid flaps are used to reconstruct hand, foot, and maxillofacial defects. Although anatomical studies of this flap pedicle have been performed on cadavers, there are no reports on the use of 320-detector row computed tomography angiography (CTA-320) to investigate the deltoid flap pedicle in living humans. This study aimed to investigate the arterial characteristics of the deltoid flap pedicle using the CTA-320 system in living humans.
METHODS
Twenty-seven adult Vietnamese patients with 54 healthy deltoid regions underwent CTA-320 to investigate arterial blood supply before clinical free-flap transfer. Two- and three-dimensional reconstruction images of the arterial pedicle were visualized, and clinical reconstruction results were evaluated.
RESULTS
The cutaneous vessel branches of the deltoid flap were separated from the posterior circumflex humeral artery (PCHA) and originated from the axillary (77.78%), subscapular (12.96%), and brachial (9.26%) arteries. The PCHA penetrated the quadrangular space in 90.74% of patients. The cutaneous arterial branch was present in the deltoid-triceps groove in 100% of patients. The average diameter and length of the PCHA were 3.38 ± 0.58 and 43.08 ± 6.60 mm, respectively. The average diameter and length of the flap cutaneous branch were 1.49 ± 0.28 and 44.57 ± 4.83 mm, respectively. The findings of CTA-320 were aligned with the intraoperative clinical findings well. All deltoid flaps were successfully free-transferred with good outcomes.
CONCLUSION
The CTA-320 is a practical and effective method for investigating deltoid flap pedicles. It enables accurate flap design and harvesting of flaps, thereby enhancing the clinical success of free-flap transfer.
PubMed: 38914111
DOI: 10.1055/s-0044-1787774 -
Journal of Hand Surgery Global Online Mar 2024Surgical reconstruction of elbow extension can help restore function in patients with tetraplegia and triceps paralysis because of spinal cord injury. Both posterior...
PURPOSE
Surgical reconstruction of elbow extension can help restore function in patients with tetraplegia and triceps paralysis because of spinal cord injury. Both posterior deltoid-to-triceps tendon transfer and transfer of the branch of the axillary nerve to the triceps motor branch of the radial nerve have been described for triceps reanimation. This systematic review aimed at reviewing current evidence in the two schools of surgery in terms of their outcome and complication profile.
METHODS
A systematic review was conducted using MEDLINE (1974-2023) and EMBASE (1946-2023) databases. The keyword terms "elbow extension," "triceps," "deltoid," "nerve transfer," "spinal cord injury," "tetraplegia," "quadriplegia," and "tetraplegic" were used in the initial search, which was supplemented with manual searches of the bibliographies of retrieved articles.
RESULTS
Twenty studies met our inclusion criteria, with 14 studies (229 limbs) on posterior deltoid-to-triceps tendon transfer, 5 studies (23 limbs) on axillary to radial nerve transfer, and 1 study (1 limb) on combined transfer. For the tendon transfer group, the majority of studies reported a median triceps power of grade 3, with a wide range of failure percentage to reach antigravity (0% to 87.5%). Common complications included gradual stretching of the musculotendinous unit, rupture of the tendon transferred, elbow contracture, and infection. For the nerve transfer group, the majority of studies also reported a median triceps power reaching grade 3. There were no reported complications or loss of power in donor action of shoulder abduction or external rotation.
CONCLUSIONS
Transfer of the axillary nerve branch to the triceps motor branch of the radial nerve in tetraplegia shows promising results, with comparable triceps muscle power compared to traditional tendon transfer and a low incidence of complication.
TYPE OF STUDY/LEVEL OF EVIDENCE
Systematic Review III.
PubMed: 38903844
DOI: 10.1016/j.jhsg.2023.11.012 -
Journal of Strength and Conditioning... Jul 2024Pexa, BS, Johnston, CD, Elder, EE, Ford, KR, Patterson, MQ, and Myers, JB. Pool-based surfboard elicits activation of posterior shoulder muscles during a surfing stroke....
Pexa, BS, Johnston, CD, Elder, EE, Ford, KR, Patterson, MQ, and Myers, JB. Pool-based surfboard elicits activation of posterior shoulder muscles during a surfing stroke. J Strength Cond Res 38(7): 1300-1304, 2024-Surfboard paddling may activate posterior shoulder muscles, which are critical to baseball pitchers' injury risk and performance. The purpose of this study was to measure posterior shoulder muscle activation during different phases of the surf stroke (propulsion vs. recovery) on a pool-based surfboard. Twenty healthy active adult subjects completed a familiarization and testing session with the pool-based surfboard. During the testing session, electromyography (EMG) sensors were placed on 6 posterior shoulder muscles: latissimus dorsi, infraspinatus, posterior deltoid, upper trapezius, middle trapezius, and lower trapezius. Subjects completed 4 laps in a pool at 3 separate resistances (low, moderate, and heavy) in a randomized order. The peak EMG signal during each phase (propulsion and recovery) was recorded. A 2-way within subject ANOVA (resistance-by-phase) with post hoc Bonferroni's corrections was used to identify differences in EMG activation. There was a significant main effect of phase for the latissimus dorsi (F = 91.3, p < 0.001), upper trapezius (F = 36.5, p < 0.001), middle trapezius (F = 33.8, p < 0.001), and lower trapezius (F = 21.6, p < 0.001). The latissimus dorsi demonstrated higher activation during the propulsion phase (p < 0.001), and all trapezius muscles demonstrated higher activation during the recovery phase (p < 0.001). There was a significant main effect of resistance for the posterior deltoid (F = 3.4, p = 0.043), with higher muscle activation in the low resistance trials compared with the heavy resistance trials (p = 0.036). Recreationally active individuals demonstrate activation of the posterior shoulder when using a pool-based surfboard. This pool-based surfboard may be beneficial to activate the posterior musculature and may be more accessible than standard surfing to baseball athletes.
Topics: Humans; Male; Electromyography; Adult; Shoulder; Muscle, Skeletal; Young Adult; Female; Water Sports; Superficial Back Muscles; Biomechanical Phenomena
PubMed: 38900176
DOI: 10.1519/JSC.0000000000004791 -
Physiological Reports Jun 2024Dynamic resistance exercise may produce reductions in pain locally at the exercising muscle and systemically at non-exercising sites. However, limited research has...
Dynamic resistance exercise may produce reductions in pain locally at the exercising muscle and systemically at non-exercising sites. However, limited research has examined these changes with multiple noxious stimuli. This study examined changes in heat pain threshold (HPT) and pressure pain threshold (PPT) on different musculature after an upper and lower body exercise to compare local and systemic effects. A crossover design with 28 participants (mean age: 21 ± 4 years, 21 female) completed three sessions. Visit one included baseline quantitative sensory testing and 5-repetition maximum (RM) testing for upper (shoulder press) and lower (leg extension) body. In subsequent sessions, participants performed upper or lower body exercises using an estimated 75% 1-RM with pre/post assessment of HPT and PPT at three sites: deltoid, quadriceps, and low back. A significant three-way interaction was observed for HPT (F (1.71, 3.80) = 2.19, p = 0.036, ηp = 0.12) with significant increases in HPT over the quadriceps (p = 0.043) after leg extension and over the deltoid (p = 0.02) after shoulder press. Significant systemic changes were not observed for HPT or PPT. Local but not systemic effects were demonstrated after an acute bout of exercise. Peripheral pain sensitivity may be more responsive to heat stimuli after resistance exercise.
Topics: Humans; Female; Pain Threshold; Male; Resistance Training; Young Adult; Adult; Muscle, Skeletal; Cross-Over Studies; Hot Temperature; Adolescent
PubMed: 38890005
DOI: 10.14814/phy2.16123 -
Operative Neurosurgery (Hagerstown, Md.) Jun 2024Vertebral artery tortuosity is a common phenomenon with an estimated incidence of 2.7%. However, it is symptomatic in very rare instances, with only 21 cases reported in...
Vertebral artery tortuosity is a common phenomenon with an estimated incidence of 2.7%. However, it is symptomatic in very rare instances, with only 21 cases reported in the literature. When a neurovascular conflict can be clearly identified, microsurgical decompression should be the treatment of choice. This can be performed through a variety of different strategies which can achieve either direct or indirect decompression. We present the case of a 68-year-old female who suffered from progressive right-sided C5 radiculopathy and deltoid weakness for over a year secondary to a neurovascular conflict between a V2 vertebral artery loop and the C5 nerve root. Microvascular decompression with vertebral artery transposition using an anterolateral approach was recommended for pain management and arrest of her neurological deficit, and the patient consented to the procedure. Institutional Review Board approval was not necessary given that this treatment was necessary and indicated. The longus colli is mobilized, and the anterior wall of the foramen transversarium is exposed. The foramen transversarium is drilled to unroof the vertebral artery. The neuroforamen is identified. A tailored foraminotomy is performed to expose the neurovascular conflict. The vertebral artery loop is dissected away from the C5 nerve root and transposed outside the neuroforamen. The transposition is maintained with Teflon felts. The patient had immediate resolution of her pain and weakness. Surgeons should be aware of this rare cause of radiculopathy and should be familiar with the surgical technique for vertebral artery mobilization. Direct decompression should be the goal of treatment when possible.
PubMed: 38888335
DOI: 10.1227/ons.0000000000001227 -
Nuclear Medicine Communications Jun 2024Fatty atrophy and fatty infiltration have been considered as limiting factors for rotator cuff repair. The metabolic activity of the muscle can be measured noninvasively...
OBJECTIVES
Fatty atrophy and fatty infiltration have been considered as limiting factors for rotator cuff repair. The metabolic activity of the muscle can be measured noninvasively by PET. In our study, we aim to compare the metabolic activity between the shoulders with rotator cuff tears and normal shoulders.
METHODS
All the patients with unilateral full-thickness rotator cuff tears were included. The patients were divided into two groups based on fatty atrophy and the metabolic activities of the rotator cuff muscles, trapezius, and deltoid were calculated using an 18F-2-deoxy-d-glucose PET-computed tomography scan for comparison.
RESULTS
A total of 17 patients were included. The standardized uptake values were compared between the affected shoulder and the normal shoulders. There was a significant increase in uptake in the insertion sites and musculotendinous junctions in the rotator cuff torn group. The standardized uptake values showed no significant difference between the low-grade and high-grade groups.
CONCLUSION
Our first hypothesis was also proven wrong; when we found that there was no statistically significant difference in the metabolic activity in muscle bellies of normal shoulders and those with rotator cuff tears. Our second hypothesis was proven wrong when found that there was no statistically significant difference in the metabolic activities of rotator cuff muscles between high-grade and low-grade fatty atrophy groups. The metabolic activities of the middle deltoid and trapezius are inversely related. Based on the findings of our study, fatty atrophy or fatty infiltration alone cannot be considered a limiting factor for rotator cuff repair.
PubMed: 38884444
DOI: 10.1097/MNM.0000000000001871 -
Cureus May 2024The deltoid ligament plays a key role in ankle stability. Ankle fractures involving the medial ligamentous complex are evaluated on the basis of medial-sided tenderness...
The deltoid ligament plays a key role in ankle stability. Ankle fractures involving the medial ligamentous complex are evaluated on the basis of medial-sided tenderness and the Ottawa ankle rules. Evolution in our understanding of this ligament over the last three decades has shown that, within this medial ligamentous complex, it is the deep deltoid ligament that confers mechanical stability. The latest evolution in this understanding, and the learning point of this report, is that only a distinct component of the deep deltoid ligament - specifically the discreet posterior third - the rear attachment of the deep deltoid ligament (RAD) - confers mechanical value. The RAD is responsible for providing the medial ligamentous component of ankle stability - specifically talar shift, tilt, and importantly rotational stability. This knowledge is of key importance in the assessment and management of ankle fractures with associated deltoid ligament injuries. In this technical report, we highlight the biomechanical contribution of the RAD, which will help surgeons and physiotherapists to accurately manage ankle injuries.
PubMed: 38883087
DOI: 10.7759/cureus.60442 -
Orthopaedic Journal of Sports Medicine Jun 2024The treatment of bony glenoid defects after anteroinferior shoulder dislocation currently depends on the amount of glenoid bone loss (GBL). Recent studies have described...
BACKGROUND
The treatment of bony glenoid defects after anteroinferior shoulder dislocation currently depends on the amount of glenoid bone loss (GBL). Recent studies have described the glenoid concavity as an essential factor for glenohumeral stability. The role of glenoid concavity in the presence of soft tissue and muscle forces is still unknown.
HYPOTHESIS
Glenoid concavity would have a major impact on glenohumeral stability in an active-assisted biomechanical model including soft tissue and the rotator cuff's compression forces.
STUDY DESIGN
Controlled laboratory study.
METHODS
In 8 human shoulder specimens, individual coordinate systems were calculated based on anatomic landmarks. The glenoid concavity was measured biomechanically and based on computed tomography. Static load was applied to the rotator cuff tendons and the deltoid muscle. In a robotic test setup, anteriorly directed force was applied to the humeral head until translation of 5 mm (N) was achieved. N was used as a parameter indicating shoulder stability. This was performed in the following testing stages: (1) intact joint, (2) labral lesion, (3) 10% GBL, and (4) 20% GBL. The 8 specimens were divided equally into 2 subgroups (low concavity [LC] versus high concavity [HC]), with 4 specimens each, according to the previously measured concavity.
RESULTS
Anterior glenohumeral stability was highly correlated with the native glenoid concavity ( = 0.8). In the testing stages 1 to 3, we found a significantly higher mean stability in the HC subgroup compared with the LC subgroup (≤ .0142). The HC subgroup still showed higher absolute N values with 20% GBL; however, there was no significant difference from the LC subgroup. The loss of stability in 20% GBL was correlated with the initial concavity ( = 0.86). Thus, a higher loss of N in the HC subgroup was observed ( = .0049).
CONCLUSION
In an active-assisted model with intact soft tissue surrounding and muscular compression forces, the glenoid concavity correlates with shoulder stability. In bony defects, loss of concavity is an essential factor causing instability. Due to their significantly higher native stability, glenoids with HC can tolerate a higher amount of GBL.
CLINICAL RELEVANCE
Glenoid concavity should be considered in an individualized treatment of bony glenoid defects. Further studies are required to establish reference values and develop therapeutic algorithms.
PubMed: 38881852
DOI: 10.1177/23259671241253836 -
Applied Ergonomics Jun 2024Many physically straining occupations involve lifting movements over the full-vertical range of motion, which over time may lead to the development of musculoskeletal...
Many physically straining occupations involve lifting movements over the full-vertical range of motion, which over time may lead to the development of musculoskeletal injuries. To address this, occupational exoskeletons can be designed to provide meaningful support to the back and shoulders during lifting movements. This paper introduces the main functional design features of the OmniSuit, a novel passive occupational exoskeleton. We present the technical and biomechanical considerations for the expected support level, as well as an evaluation of the physiological benefit and usability of the exoskeleton in a sample of 31 healthy volunteers performing physically demanding tasks in a laboratory setting. The OmniSuit exoskeleton significantly reduced Deltoid, Trapezius and Erector Spinae muscle activity between 4.1%MVC and 15.7%MVC when lifting a 2.5kg weight above shoulder level (p<0.001), corresponding to a reduction of up to 49.1% compared to without exoskeleton. A position-dependent reduction of Erector Spinae muscle activity was observed (p<0.001), with reductions ranging between 4.6%MVC and 14.0%MVC during leaning and squatting, corresponding to a reduction up to 41.5% compared to without exoskeleton. The measured muscular support and the predicted support torque based on the biomechanical model were found to show a similar profile for those phases of the movement which are most straining to the shoulder and back muscles. Participants reported experiencing good device usability and minimal discomfort (<1/10) in the shoulder and back during task execution with exoskeleton support. These first results validate that the considered biomechanical model helped design an ergonomic and efficient exoskeleton, and confirm the potential of such wearable assistive devices to provide support over multiple joints during physically demanding tasks.
PubMed: 38876001
DOI: 10.1016/j.apergo.2024.104332 -
Journal of the Mechanical Behavior of... May 2024The rotator cuff tear effects on glenohumeral joint tissues, such as superior labrum anterior-posterior (SLAP) lesions, have been studied experimentally or numerically...
The rotator cuff tear effects on glenohumeral joint tissues, such as superior labrum anterior-posterior (SLAP) lesions, have been studied experimentally or numerically in various cases. In relation to these studies, and as a novel feature of our study, infraspinatus (INF) muscle tear effects on other muscle force variations and stress and strain increases on glenoid labrum (GL), glenoid cartilage (GC) tissues, and a SLAP pathology were investigated. The ITK-SNAP Software (ISS) was used to segment the humerus and glenoid bone. The surface entities were segmented and exported to SolidWorks 2019, where the finite element model (FEM) was completed. Static optimizations of the muscle forces were calculated using a generic model in OpenSim 4.1 for the 0-3.88 s time interval to perform our finite element analyses (FEAs) in ANSYS 19.3 for the intact, partial torn, and fully torn INF muscle. The FEAs were also conducted for the specified time interval. The stress and strain increases on the GL, and GC tissues were determined to be critical when compared with yield strengths. In the case of fully torn INF, the GL and cartilage interfacial principal stress was calculated to be 3.3856 MPa. In the case of the fully torn INF, the principal stress that occurred on the GC tissue was calculated to be 42.465 MPa. In the case of the intact INF, the principal stress that occurred on the labrum was obtained as 4.257 MPa. These results showed that there was no detachment or disorder on the designated tissues caused by the INF muscle tear when the shoulder functioned at 60° of external rotation at 11° of abduction. Nonetheless, a minor amount of external force could cause severe pathological effects on the specified tissues.
PubMed: 38870586
DOI: 10.1016/j.jmbbm.2024.106600